well basically female (tend) to have shorter fins than males. but it isn't always the case, some males called "Plakats" have short fins. so the tell a difference from a female and a Plakat male is an "egg spot" it is where the eggs come out of the female when breeding. it should be located on the belly or between the ventral fins (same area). then the "beard" is noticable if you have a male, sometimes it doesn't sometimes it does, it is noticable without flaring, males also tend to flare more "larger" then females. where the span of it goes wider (the gills), females hardly open sometimes.